WAEC SSCE - Geography - 2012

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Isotherms are lines drawn on maps joining places having equal temperature. In other words, they connect points on a map that have the same temperature. They are useful in visualizing temperature patterns and variations across different regions, and are commonly used in weather forecasting and climatology. By looking at isotherm maps, we can see where the hottest and coldest areas are located, as well as the temperature gradients and fronts.

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The outer layer of the solid earth is called the crust. Think of the earth like an apple: the crust is the thin, outermost layer, while the core is the dense, central part. The crust is made up of solid rock and is the part of the earth that we live on. It is relatively thin compared to the other layers, only about 10-50 kilometers thick depending on where you are on the planet. The crust is also divided into several large pieces, called tectonic plates, which can move around and sometimes collide with each other, causing earthquakes and volcanic activity. Overall, the crust plays a crucial role in supporting life on earth by providing a stable surface for us to live and grow on.

Maelezo ya Majibu

Maelezo ya Majibu

Convectional rains are typical in equatorial areas. This is because in equatorial areas, there is a lot of solar radiation that heats the ground surface, which in turn heats the air above it. The heated air rises and as it rises, it cools, condenses and forms clouds. These clouds lead to convectional rainfall. This type of rainfall is common in equatorial areas which experience high temperatures and humidity throughout the year.

Maelezo ya Majibu

Maelezo ya Majibu

The term that describes a piece of land almost surrounded by water is called a peninsula. A peninsula is a piece of land that is surrounded by water on three sides, while the fourth side is connected to the mainland. Examples of peninsulas include Florida in the United States, the Iberian Peninsula in Europe, and the Arabian Peninsula in the Middle East. The word 'peninsula' is derived from the Latin words 'paene' meaning 'almost' and 'insula' meaning 'island'.

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Of the given options, granite is an igneous rock. Igneous rocks are formed by the solidification of magma or lava. Granite is a coarse-grained intrusive igneous rock composed of minerals such as quartz, feldspar, and mica. Sandstone, chalk, and limestone are sedimentary rocks formed from the accumulation of sediment over time.

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The wearing away of the sides and bottom of a river channel is called corrasion. This process is also known as abrasion and involves the scraping and rubbing of rock material against the river bed and banks, which results in the erosion of the channel. The particles that cause corrasion include pebbles, sand, and boulders that are transported by the river. Corrasion is one of the major processes responsible for the formation of river valleys and the alteration of river channels over time.

Maelezo ya Majibu

Maelezo ya Majibu

The low population density in the middle belt of West Africa resulted from all the following except "inadequacy of food in the area." The other options - unfavorable climate, absence of heavy industries in the area, and inadequate infrastructure - may have contributed to the low population density in the middle belt of West Africa, but the lack of adequate food in the area is not one of the reasons. The region is known for its fertile soils, and agriculture is a major economic activity, with crops such as millet, sorghum, and cowpeas being grown in large quantities. Therefore, it is unlikely that the area would have a low population density due to inadequate food.

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Rainfall is not associated with human intervention. Rainfall is a natural process that occurs due to the water cycle in the atmosphere. It involves the evaporation of water from the surface of the earth, which rises into the atmosphere and condenses into clouds. The clouds then release water in the form of rain, which falls back to the surface of the earth. Mining, construction, and urbanization, on the other hand, are all activities that involve human intervention and can have significant impacts on the environment.

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Deciduous trees are those that generally shed their leaves during one season of the year. This is usually in autumn or fall, before winter, in response to changes in the length of daylight and temperature. Shedding their leaves allows the tree to conserve water and energy during the winter months when there is less sunlight and lower temperatures. In contrast, evergreen trees do not shed their leaves at any season of the year and retain their leaves throughout the year.

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The difference between the temperatures of the hottest and coldest months of a place is known as the "annual range of temperature". This refers to the difference between the highest and lowest temperatures experienced over the course of a year in a specific location. For example, a place that experiences very hot temperatures in the summer and very cold temperatures in the winter will have a larger annual range of temperature than a place where temperatures are more consistent throughout the year. Therefore, the correct option is "annual range of temperature".

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When there are large scale horizontal earth movements and stresses in the Earth's crust, fold mountains may occur. These are mountains that form when rock layers are pushed up and folded due to the movement of tectonic plates. They often occur in areas of convergent plate boundaries, where two plates are pushing against each other, causing the rock layers to buckle and fold. Block mountains, on the other hand, are formed when large areas of the Earth's crust are uplifted and separated from surrounding areas due to faults or fractures in the Earth's crust. Volcanic mountains are formed by the accumulation of volcanic material, while residual mountains are formed by the weathering and erosion of existing mountains.

Maelezo ya Majibu

Maelezo ya Majibu

The major advantage of plantation agriculture in East Africa is that it provides a regular supply of raw materials. Plantation agriculture involves the large-scale cultivation of a single crop, such as tea or coffee, on a large tract of land. These crops are grown primarily for export, providing a regular source of foreign exchange for the countries that produce them. The regular supply of raw materials is important for both the local economy and the global economy. In the local economy, it provides a reliable source of income and employment for the people who work on the plantations and in related industries. In the global economy, it ensures a steady supply of raw materials for manufacturers and consumers around the world. Overall, plantation agriculture has played a significant role in the economic development of East African countries, providing a reliable source of income and contributing to global trade.

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The correct answer is "weathering". Weathering is the process by which rocks are broken down into smaller fragments or particles through physical, chemical, and biological means. These broken-down rock particles remain in place and do not get transported away. Weathering can occur through a variety of mechanisms including freeze-thaw cycles, chemical reactions, and plant root growth. It is an important process in the formation of soil and can also lead to the development of unique landforms.

Maelezo ya Majibu

Maelezo ya Majibu

The environmental lapse rate is a decrease of temperature by 6.50°C for every 1,000 meters of ascent. This means that as you climb higher in the atmosphere, the temperature decreases by approximately 6.50°C for every 1,000 meters you ascend. This phenomenon occurs because as you move away from the surface of the earth, there is less heat available from the sun to warm the air. Additionally, the air at higher altitudes is less dense and can hold less heat, leading to a decrease in temperature. The environmental lapse rate is an important concept in meteorology and helps us understand how temperature changes with altitude.

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The satellite of the Earth is the Moon. The Moon is a natural satellite of the Earth, meaning it is a celestial body that orbits around the Earth. It is the fifth largest moon in the solar system and the largest among planetary satellites relative to its host planet. The Moon is an important celestial object that affects the Earth's tides, provides a natural satellite for scientific study, and is the only celestial body beyond Earth that has been visited by humans.

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A bedding plane is a characteristic of sedimentary rocks. It refers to the boundary between two layers or beds of sedimentary rocks, which are formed by the accumulation of sediment over time. These layers or beds are usually parallel to each other and can vary in thickness and composition. Bedding planes are an important feature for geologists as they provide clues about the environment in which the sediment was deposited and the history of the area. For example, the thickness and composition of the beds can indicate changes in the water depth, the type of sedimentary environment, or the occurrence of major geological events such as earthquakes or volcanic eruptions. In contrast, igneous and metamorphic rocks do not have distinct bedding planes as they are formed from molten materials and subjected to intense heat and pressure, which cause the minerals to recrystallize and fuse together into a solid mass. Volcanic rocks, on the other hand, may have distinct layers or bands of lava flows or ash deposits, but these are not considered bedding planes.

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The Mediterranean vegetation is described as xerophytic vegetation because it is drought resistant. The Mediterranean region is known for its hot and dry summers, and mild and rainy winters. The vegetation in this region has adapted to the dry conditions by developing various mechanisms to conserve water, such as small and thick leaves, deep roots, and succulent stems. This adaptation allows the vegetation to survive the long periods of drought that are common in the Mediterranean climate. Therefore, the term xerophytic, which means "dry-loving," is used to describe the vegetation of the Mediterranean region.

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Steep sides and often dry valleys in the desert are called "wadis". Wadis are usually formed by water erosion and are characterized by a wide, flat bottom and steep sides. During the rainy season, water flows through wadis and creates a temporary stream. However, during dry seasons, wadis are often dry, and they are used as pathways for human and animal migration in the desert. The term "wadi" is used primarily in the Middle East and North Africa.

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Deltas are landforms formed at the mouth of a river where it meets an ocean, sea, or lake. Therefore, they are not associated with the upper course of a river. Meanders are bends or curves in a river channel that form as the water flows. While they can occur in any part of a river, they are most commonly found in the middle and lower courses. Therefore, they are not associated with the upper course of a river. Rapids are sections of a river where the water flows rapidly over rocks or a steep gradient, creating turbulence and white water. They are typically found in the upper course of a river, where the gradient is steeper and the water flows faster. Gorges are narrow, steep-sided valleys that form as a river cuts through hard rock. They are also commonly found in the upper course of a river, where the gradient is steeper and the river is more erosive. Therefore, the pair associated with the upper course of a river are II and IV, which correspond to gorges and rapids, respectively.

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Re-afforestation and planting of trees on windbreak is the method that will best help to check wind erosion. This is because the trees act as windbreaks by reducing the velocity of the wind, and hence its erosive power. As a result, the soil is protected from being carried away by the wind. Additionally, the trees also stabilize the soil by increasing its porosity and retaining moisture, which further reduces the susceptibility of the soil to wind erosion. Inter-cropping and contour ploughing, strip cropping and crop rotation, and contour ploughing and manuring are also useful techniques for soil conservation but are not as effective in checking wind erosion as planting of trees on windbreaks.

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Precipitation refers to any form of moisture that falls from the atmosphere to the earth's surface. It includes rain, snow, sleet, and hail. Therefore, out of the options given, the correct answer is "dust." Dust is not a form of precipitation, but it can be suspended in the air and transported by wind currents. Dew and fog are not considered precipitation either, as they are formed through the condensation of moisture in the air rather than through the falling of moisture from the atmosphere.

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A vertical section of soil through all its horizons is called a soil profile. It is a representation of the layers or horizons of soil from the surface downwards to the bedrock. The soil profile helps to provide information about the soil's properties, including its texture, structure, nutrient content, and depth, which is important for agricultural and environmental purposes. By examining the soil profile, scientists can understand the physical and chemical characteristics of different layers and how they interact to support plant growth and other ecological functions.

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Mechanical weathering due to changes in temperature occurs mainly in desert regions. This is because in desert regions, temperatures are very high during the day, and very low at night. This results in the expansion and contraction of rock surfaces, causing them to crack and break down. The daily temperature fluctuations cause repeated expansion and contraction, which leads to the breakdown of rocks into smaller pieces. This type of mechanical weathering is called thermal stress weathering or insolation weathering. In wet equatorial regions, chemical weathering due to the action of rainfall and high temperatures is more common. In coastal areas and polar regions, other forms of mechanical weathering, such as abrasion and freeze-thaw weathering, respectively, are more prevalent.

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The most valuable products of equatorial forests are cocoa, rubber, and oil palm. These crops are well-suited to the hot, humid climate of the equatorial regions and are important exports for many countries. Cocoa is used to make chocolate and is in high demand all over the world. Rubber is a versatile material used in the production of various products such as tires, rubber gloves, and footwear. Oil palm is a source of edible oil and is also used in the production of biofuels. While tea, bananas, oranges, cassava, plantain, rice, ginger, coffee, and sisal are also grown in equatorial regions, they are not considered to be as valuable as cocoa, rubber, and oil palm. These crops may be important for local consumption, but they do not have the same level of international demand and economic impact as the three primary crops mentioned above.

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A ginnery is a place where cotton is processed to take out the seed. Cotton from the farm is brought to the ginnery, where it undergoes a process called ginning. During ginning, the seeds are removed from the cotton fibers, leaving only the fiber which can be spun into yarn or thread. After ginning, the cotton is then baled and transported for further processing or storage.

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Convectional rains are typical of equatorial areas. Convectional rainfall occurs when the sun heats the ground, causing the air above to become warm and rise. As the warm air rises, it cools and condenses, forming clouds. The clouds continue to grow until they can no longer hold the water droplets, which then fall as rain. In equatorial areas, where the sun's rays are most intense, the heating and rising of warm air is more common, leading to frequent and heavy convectional rainfall.

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Winds blow from areas of high pressure to areas of low pressure. This is because air moves from a region of higher air pressure to a region of lower air pressure, resulting in the movement of air, which we perceive as wind. The greater the difference in pressure, the stronger the wind. Therefore, the statement that is true of winds is that they blow from areas of high pressure to areas of low pressure. The other statements are not true.

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The option that is not a characteristic of the rainforest is "it has deciduous trees and aerial roots." Explanation: A rainforest is a dense forest characterized by high annual rainfall, high humidity, and high biodiversity. One of the notable features of a rainforest is that it has tall trees with buttress roots and evergreen broad leaves that form a dense canopy. The trees in the rainforest are also arranged in different heights and layers of canopies, which is necessary to absorb sunlight. Additionally, some trees in the rainforest are climbers, creepers, and epiphytes. However, deciduous trees and aerial roots are not typical of the rainforest. Deciduous trees shed their leaves during the dry season, which is uncommon in the rainforest, while aerial roots are more common in mangroves and swamps, which are different from the rainforest ecosystem.

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The industry that is best located near the source of raw material is sugar refining. Raw sugar is extracted from sugarcane, which is grown in tropical and subtropical regions. Because of the high perishability of sugarcane, it needs to be processed into sugar as soon as possible after it is harvested. This means that sugar refineries need to be located near the source of raw sugarcane to minimize transportation time and costs, and to ensure the sugar can be processed quickly. Additionally, transporting raw sugarcane over long distances can result in spoilage and a reduction in sugar content. Therefore, the sugar refining industry is best located near the sugarcane fields to ensure the production of high-quality sugar at a lower cost. Other industries such as drug manufacturing, paint manufacturing, and watch making do not require raw materials that are as perishable or time-sensitive as sugarcane, so they may not need to be located as close to the source of raw materials.

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Maelezo ya Majibu

High population growth is when the number of births in a population exceeds the number of deaths. In other words, when the birth rate is higher than the death rate, the population will continue to grow. This means that the population is increasing at a fast rate, which can have significant impacts on resources, infrastructure, and the environment. Therefore, option D, "the birth rate is higher than the death rate," is the best description of high population growth.

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Lumbering in Zaire (Democratic Republic of Congo)

(I) Favourable factors

• Extensive tropical rainforest: The Congo Basin is covered by dense equatorial forest containing large quantities of valuable hardwoods such as mahogany, ebony and iroko.
• Hot, wet equatorial climate: High temperatures and heavy, well-distributed rainfall throughout the year encourage rapid and continuous tree growth.
• Presence of navigable rivers: The River Congo and its tributaries provide cheap water transport for floating logs to sawmills and ports.
• Availability of labour: A large local population supplies the labour needed for felling and hauling timber.

(II) Problems of exploitation

• Dense undergrowth and mixed forest: Valuable trees grow scattered among many useless species, making selective felling difficult and costly.
• Poor land transport: Few roads and railways, coupled with the swampy terrain, make it hard to move logs to processing centres.
• Heavy hardwoods: Many tropical hardwoods do not float easily, adding to transport difficulty.
• Pests, diseases and climate: The hot, humid climate breeds pests and diseases (such as those spread by the tsetse fly) that affect workers and hinder operations.
• Shortage of capital and skilled labour: Inadequate funds and few trained workers limit large-scale mechanised lumbering.

(III) Contributions to the economy

• Foreign exchange: The export of timber and wood products earns foreign currency.
• Employment: Felling, sawmilling and transport of timber provide jobs for many people.
• Raw materials: It supplies timber for construction and raw materials for furniture and paper industries.
• Development of infrastructure: Lumbering encourages the building of roads and the growth of towns in forest areas.
• Government revenue: Royalties and taxes on timber add to government income.

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(a) Outline map of Africa

(b) Importance of African rivers

1. Hydro-electric power generation: Rivers provide water for dams and hydro-electric power stations. Examples include the Aswan High Dam on the Nile, Kainji Dam on the Niger and Akosombo Dam on the Volta.
2. Irrigation: River water is used to irrigate farms, especially in dry regions. For example, the River Nile supports irrigation farming in Egypt and Sudan.
3. Domestic and industrial water supply: Rivers supply water for drinking, washing, cooking, watering livestock and for industrial processes.
4. Transport and communication: Navigable rivers provide relatively cheap routes for moving people and goods, particularly where roads and railways are poorly developed.
5. Fishing and employment: Rivers provide fish, crayfish, crabs and other aquatic products for food. They also provide employment for fishermen, fish processors, canoe builders and traders.
6. Fertile floodplains: During flooding, rivers deposit fertile alluvium on their floodplains. This encourages intensive cultivation of crops.

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(a) Five problems of development of the Cross River Basin

• Shortage of capital: The huge cost of building dams, roads and other facilities is difficult to raise.
• Dense forest and difficult terrain: The thick tropical rainforest and rugged, swampy land make clearing and construction slow and expensive.
• Heavy rainfall and flooding: Very high rainfall causes flooding and erosion, which damage farms, roads and structures.
• Poor transport and inaccessibility: Bad roads and few bridges make movement of people, materials and produce difficult.
• Pests and diseases: The humid environment breeds pests and disease vectors (such as tsetse fly and mosquitoes) that affect labour, crops and animals.
• Shortage of skilled manpower: Few trained personnel are available to plan and execute development projects.

(b) Five ways these problems can be solved

• Provision of funds: Government should provide adequate funds and attract loans and foreign investment to finance projects.
• Construction of roads and bridges: Good roads and bridges should be built to improve accessibility.
• Flood and erosion control: Dams, drainage channels and afforestation should be used to control flooding and erosion.
• Control of pests and diseases: Vector control, drainage of swamps and provision of health facilities should be undertaken.
• Training of manpower: Skilled workers should be trained and experts employed to plan and manage development.
• Clearing and land preparation: Use of modern machinery to clear the forest and prepare the land for farming and settlement.

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(a) Advantages and disadvantages of air transportation

Three advantages

• It is the fastest means of transport, so it saves time over long distances.
• It can cross difficult terrain such as mountains, deserts, forests and oceans that other means cannot easily cross.
• It is comfortable and suitable for carrying perishable, urgent and light valuable goods, and for emergencies.

Two disadvantages

• It is very expensive, both to build/maintain (airports and aircraft) and for passengers to use.
• It carries only limited quantities of goods and cannot conveniently carry bulky, heavy cargo; it is also affected by bad weather and accidents are often fatal.

(b) Five roles of road transportation in promoting economic development

• Movement of goods and people: Roads move raw materials, finished goods, farmers and workers from one place to another, linking areas of production to markets.
• Opening up of rural areas: Roads reach remote interior areas that other means cannot, opening them up for farming, mining and trade.
• Promotion of trade and commerce: Good roads encourage the exchange of goods between regions and support market activities.
• Employment: Road construction, maintenance, haulage and transport services provide many jobs.
• Growth of towns and industries: Roads attract industries and encourage the growth of settlements along their routes.
• Feeder to other transport: Roads link farms, homes and factories to railways, seaports and airports.

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(a) Sketch map of Nigeria

Key locations shown: Niger Delta, Kainji Lake, Lokoja (confluence town), and Jos Plateau.

(b) Physical factors limiting river transportation in Nigeria

1. Waterfalls, rapids and cataracts: These interrupt river channels and prevent the smooth movement of vessels.
2. Seasonal fluctuation in river volume: Water levels are low in the dry season, making channels shallow, while some rivers flow swiftly and flood during the rainy season.
3. Silting and sand bars: Deposition of silt and sand reduces the depth of river channels and obstructs boats.

Other acceptable factors include floating water weeds, debris, narrow channels and gorges, deltaic river mouths, and short river courses.

(c) Solutions to the limiting factors

1. Dredging: River beds should be dredged regularly to remove silt and sand bars and maintain a deep navigable channel.
2. Construction of dams, locks and canals: Dams regulate water flow, while locks or canals enable vessels to bypass rapids, cataracts and waterfalls.
3. Clearing obstructions: Water weeds and floating debris should be removed continuously from navigable channels.

Other measures include channelization, the use of small or light vessels on shallow rivers, and construction of road or rail routes around major rapids and waterfalls.

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(a) Map of West Africa

Key: shaded area = French-speaking country (Senegal); hatched area = English-speaking country (Ghana); ● = national capital.

(b) Objectives of ECOWAS

1. To promote economic co-operation and integration among member states.
2. To promote trade among member states and work towards a common market.
3. To encourage the free movement of people, goods, services and capital within West Africa.

(c) Problems hindering the achievement of ECOWAS objectives

1. Language differences: English-, French- and Portuguese-speaking countries often experience communication and administrative difficulties.
2. Different currencies: the use of separate national currencies makes payments and trade between member states difficult.
3. Poor transport and communication: inadequate roads, railways, ports and communication links restrict the movement of people and goods.

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(a) Outline map of Nigeria showing Abuja and three savanna vegetation belts

Key: Abuja is marked by a solid dot (●). The savanna belts are Guinea savanna, Sudan savanna and Sahel savanna.

(b) Contributions of forest vegetation to the Nigerian economy

1. It provides timber, poles and other wood for building, furniture-making and boat-building.
2. It supplies firewood and charcoal used as domestic fuel.
3. It provides raw materials for industries, for example palm oil for soap-making, rubber, wood pulp and raffia.
4. It provides employment and income for lumbermen, sawmill workers, forest guards and traders in forest products.
5. It earns government revenue through licences, royalties and taxes on forest products.
6. It earns foreign exchange through the export of timber, rubber, palm produce and other forest products.
7. It provides food and medicinal products such as fruits, nuts, honey, snails and herbs.
8. Forest reserves and wildlife support tourism and recreation.

(c) Problems hindering exploitation of forest vegetation in Nigeria

1. Poor accessibility: Dense forest, swampy land, poor terrain and inadequate motorable roads make it difficult and expensive to reach and evacuate logs.
2. Mixed tree species: Valuable trees occur scattered among less useful species; consequently, surveying and selective logging are costly.
3. Inadequate capital and machinery: Modern equipment for felling, hauling, processing and transport is expensive and often insufficient.
4. Depletion of forests: Deforestation, bush burning and shifting cultivation have reduced the stock of economic trees in many areas.

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(a) Four differences between urban and rural settlements

(b) Four favourable conditions for the growth of settlements

• Availability of water: A reliable supply of fresh water for domestic, agricultural and industrial use attracts and sustains settlement.
• Fertile soil: Good soils for farming encourage people to settle and produce food.
• Good transport and accessibility: Sites with good roads, railways or navigable rivers attract people and trade.
• Availability of employment/industries: The presence of industries, mines or commercial activities that provide jobs draws people to settle.
• Security and level land: Peaceful, secure areas with gentle, well-drained relief that is easy to build on encourage settlement growth.

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(a) Three factors responsible for the dominance of light industries in developing countries

• Shortage of capital: Light industries need relatively little capital to establish and run compared with heavy industries, so they suit the low investment capacity of developing countries.
• Low level of technology and skills: Light industries use simpler machinery and less skilled labour, which matches the limited technical know-how available.
• Small local market and low purchasing power: The market mostly demands consumer goods such as food, textiles and beverages, which light industries produce, rather than expensive heavy goods.
• Availability of agricultural raw materials: Many light (agro-based) industries process locally available farm produce such as cotton, cocoa and oil palm.

(b) Four advantages of the concentration of industries in an area

• It allows industries to share common infrastructure such as roads, electricity and water, thereby reducing cost.
• It provides a large pool of skilled and unskilled labour from which firms can draw.
• Industries can supply raw materials and semi-finished goods to one another (linkages), saving transport cost.
• It creates a large local market and supporting services such as banks, repair workshops and insurance.
• It encourages exchange of ideas and technology among firms, improving efficiency.

(c) Three disadvantages of the concentration of industries

• It causes overcrowding, traffic congestion and pressure on housing and social amenities.
• It leads to serious pollution of air, water and land in the concentrated area.
• It creates regional imbalance, since other areas remain undeveloped and depopulated as people migrate to the industrial zone.